Apparatus for stacking material and automatically feeding the material to a worktable of a paper-cutting machine



Aug. 27, 1968 R. MOHR 3,398,841

APPARATUS FOR STACKING MATERIAL AND AUTOMATICALLY FEEDING THE MATERIAL TO A WORKTABLE OF A PAPER- CUTTING MACHINE 5 Sheets-Sheet 1 Filed Feb. 7, 1967 Aug. 27. 1968 R. MOHR 3, 4

APPARATUS FOR STACKING MATERIAL AND AUTOMATICALLY FEEDING THE MATERIAL TO A WORKTABLE OF A PAPER-CUTTING MACHINE Filed Feb. 7, 1967 5 Sheets-Sheet 2 Aug. 27. 1968 R. MOHR 3,398,841

APPARATUS FOR STACKING MATERIAL AND AUTOMATICALLY FEEDING THE MATERIAL To A WORKTABLE OF A PAPER-CUTTING MACHINE Filed Feb. 7, 1967 5 Sheets-Sheet 5 Fig.4.

United States Patent 3,398,841 APPARATUS FOR STACKING MATERIAL AND AUTOMATICALLY FEEDING THE MATERIAL TO A WORKTABLE OF A PAPER-CUTTING MACHINE Rudolf Mohr, Hattersheimerstrasse, Hofheim, Taunus, Germany Filed Feb. 7, 1967, Ser. No. 614,474 8 Claims. (Cl. 214-85) ABSTRACT OF THE DISCLOSURE Material handling apparatus in which a plurality of stacks of aligned material are superposed on a lift support with hollow boards interposed between successive stacks. The lift support is raised until the uppermost board reaches the height of a worktable, at which point an air supply conduit delivers compressed air to the uppermost hollow board and the raising of the lift support is terminated. The uppermost stack of material can then be automatically conveyed to the worktable on a cushion of air.

BRIEF SUMMARY OF THE INVENTION The invention is directed to the handling of stacks of paper material which are to be cut in cutting machines.

Before the material to be cut is supplied to the worktable of a paper-cutting machine, it is shaken in known manner on so-called shaker tables, in order thereby to align exactly the separate sheets relative to one another, so that exact cut sizes are produced when the stack is cut.

In order that the separate component stacks ares not disturbed during their feed to the worktable of the papercutting machine, so that the sheets do not change the position they have assumed after the shaking operation, it is known to mount the paper stacks on separate hollow bodies which are provided with nozzles through which compressed air is discharged, so that the stacks slide on an air cushion as they are fed to the worktable.

It is also known to position a hollow metal or plastic sheet, to which compressed air can be admitted, between the separate stacks, in order to enable easy displacement of these component stacks from the stack support.

With these known arrangements, however, when a component stack is lifted from the stack support, the latter must always be connected by manual actuation to the air supply and the stack must be brought manually to the required working position.

An arrangement is also known which consists of a gripper device operated by air pressure for feeding a component stack to the cutting table of a paper-cutting machine. However, this gripper is not controlled in synchronism with the movement of the stack lift, but can be introduced at any point into the stack of sheets. Consequently, the danger always exists of slippage of the layer of sheets as the com-ponent stack is pushed away, so that it is always necessary to re-straighten the layers of sheets fed to the cutting table.

An object of the present invention is to provide a means by which it is possible for stacks of paper straightened on the shaker table to be supplied automatically to the stacker and for the stack to be brought fiom the stacker to the worktable of a paper-cutting machine. According to the invention, this is achieved with a stacking means for material to be cut and with a mean-s for automatically feeding the stacks to the cutting machine by the interposition of hollow boards between successive stacks, for example, on a stacking lift, each board being connected to an air supply nozzle which is flush with the working table when such board reaches the height thereof, the said nozzle being 3,398,841 Patented Aug. 27, 1968 operative to release the supply of air to the board accommodating the stack, so that the material to be out can be automatically conveyed by means of synchronously controlled grippers to the working table. The air supply nozzle or pipe is provided with a sealing bell which can be connected to the air supply opening of the board, the said bell controlling a limit switch for the release or the connection of the air supply. The board consists of a hollow body through which ribs extend, the air supply opening of said body being arranged in a laterally projecting extension. If the bell of the air supply pipe comes into :a position bear ing against the extension of the air board when the stacking lift is benig raised, the bell is displaced against the action of a spring and the limit switch is operated by an abutment surface to release the supply of air to the board. At the same time, the raising of the stacking lift is stopped by the operation of the limit switch. Since the bell is arranged to be flush with the machine table when the switch is activated, the upper surface of the board is likewise automatically brought to the same height as the machine table, so that now the paper stack on the board can be brought to the worktable by means of grippers which can, for example, be controlled by the saddle plate of the paper-cutting machine.

The control of the gripper or grippers can be effected in such a way that a contact is closed through a limit switch when the feeding saddle plate reaches an end position, which contact sets in operation the movement of the gripper for the displacement of the paper stack to the machine table.

The loading of the machine can be effected from the front side or even from the rear side of the machine table. When the loading is effected from the rear side of the machine table, the arrangement is such that a lateral gliding rule or arm of the machine table is lowered, so that the paper stack can be fed without obstruction to the machine table until in abutment with the feeding saddle plate. During this travel, the paper stack rests on an air cushion, so that the position of the sheets as taken up during the shaking operation is assured.

The means according to the invention provides for the possibility of effecting a reserve stacking, so that in use, it is merely necessary to bring the separate stackers to the required position for the stack supply, whereupon the supply and the loading of the machine is effected in a fully automatic manner. In the rest position, in which the bell does not contact the air supply opening of the board, the air supply is shut off so that during the lifting operation, slipping of the stack on the air board is impossible. Consequently, it is always reliably insured, during the travel from the shaker device, until it is in abutment with the feeding saddle plate and is satisfactorily positioned for the cutting operation.

The invention is hereinafter more fully explained with reference to the embodiment which is shown in the appended drawing.

BRIEF DESCRIPTION OF THE DRAWING FIGURE 1 is a side elevation view of a cutting machine with a stacking lift accommodating a paper stack;

FIGURE 2 shows the feeding of a stack of sheets from a shaker table to the stacking lift;

FIGURE 3 is a sectional view on enlarged scale through a nozzle for supplying compressed air to the air board; and

FIGURE 4 is a plan view of a part of the air board.

DETAILED DESCRIPTION OF THE INVENTION As seen in FIG. 1, a stacking lift 1 is arranged on the side of a paper-cutting machine 2. Component stacks 4, 5, 6, 7 of material to be cut are positioned on a pallet 3 with interposed hollow boards 8, 9, 10, 11. In the position as shown, the component stack 7 has reached a height at which feeding onto the machine table 12 can take place.

An air supply pipe 13 is arranged with its lower end 14 in exact alignment with the surface of the machine table 12. When the hollow board 11 contacts the underside 14 of the pipe 13, as will hereinafter be more fully described, the vertical movement of the lift is terminated and at the same time a pressure air supply is placed in communication with the board 11 which applies the air'pressure on the stack 7 so that the stack now rests on an air cushion. A gripper or grippers (not shown), which can be controlled by way of the feeding saddle plate, now engages the stack 7 and feeds the latter to the machine 12. The feeding of the stack can be effected both from the front side or from the rear side of the machine. After the stack 7 is removed from the board 11, the said board is removed. As a result, the stacking lift can once again carry out upward movement until a bell or cap member 15 in the supply pipe 13 comes into contact with the next lower board 10. In this position, the bell 15 communicates with the air supply opening 16 of the board 10 (see FIG. 4), so that compressed air can flow through the pipe 13 into the interior 17 of the board which is provided with ribs 18 to pass through the nozzles 19 beneath the paper stack 6. In this way, the said paper stack is free for being transferred onto the machine table 12.

The air supply pipe 13 accommodates the sealing bell 15, which has an insert 20 of resilient material. The resilent insert forms a sealed connection between the uppermost board and the bell 15. The bell or cap member 15 is secured to the pipe 21 and is subjected to the action of a spring 22. If the cap member 15 is displaced with the pipe 21 against the action of the spring 22, then a bearing surface of abutment 23 actuates a limit switch 24. The limit switch is connected in a powder supply circuit for the lift drive means such that when the switch is activated the drive means is deenergized and the raising of the lift is terminated. The limit switch 24 also controls the supply of pressure air to a conduit 25 as, for example, by controlling the operation of a valve such that when the switch is activated the valve is operated to admit pressure air to conduit 25. Thereby, when the switch is activated, pressure air flows from conduit 25 to the uppermost board via pipe 21 and cap 15. If the cap 15 returns to the lower end position (FIG. 3) under the action of the spring 22, the switch 24 is re leased, so that the lifting movement of the lift 1 is resumed. Simultaneously, the air supply from the pipe 25 through the pipe 21 is interrupted.

FIG. 2 shows a shaker table 26 from which a stack 27 is conveyed to the lift. In the position as shown, the board 28 is in abutment with the pipe 13, so that, as previously described, compressed air is supplied to the board 28 and the lifting movement of the stacking lift is interrupted. The stack 27 can now be displaced to the board 28 on an air cushion. FIG. 2 shows how the last stack is fed from the shaker table to the stacking lift. In this position, the upper surface of the board 28 assumes the same height as the surface of the machine table 12. The superimposed stacks are now ready for being successively removed and fed to table 12.

What is claimed is:

1. Handling apparatus for stacks of material comprising support means for a plurality of superimposed stacks of material, hollow boards supporting respective stacks of material and interposed between successive stacks of material, said support means being lowerable to permit placement thereon of superimposed stacks of material, and raisable to permit successive removal of stacks of material at a particular level, pressure fluid supply means supported at a predetermined level, each said hollow board having an inlet forpressure fluid in a region outside the stacked material and a plurality of outlets distributed beneath the stacked material, said boards being oriented with their inlets in substantially vertical alignment with said supply means such that as the support means is raised the uppermost of the boards contacts the pressure fluid supply means, and operating means coupled to said pressure fluid supply means and operative to sense contact of the uppermost board with the pressure fluid supply means for controlling admission of pressure fluid to such hollow board and for interrupting the raising of the support means.

2. Apparatus as claimed in claim 1, comprising a worktable for receiving stacks of material, said fluid supply means having an outlet at the level of said worktable.

3. Apparatus as claimed in claim 2, wherein said fluid supply means comprises a cap member adapted for contacting the uppermost board at the inlet thereof, spring means acting on said cap member and urging the same to an initial extended position, said cap member being displaceable against the action of said spring means as the uppermost board is raised in contact therewith, said operating means comprising switch means which is actuable when the cap member has been raised a predetermined distance for interrupting the raising of the support means and for admitting pressure fluid to the uppermost board via said cap member.

4. Apparatus as claimed in claim 3, wherein said pressure fluid supply means comprises a fluid supply conduit, and a second conduit secured to said cap member for displacement therewith and slidably mounted on said fluid supply conduit.

5. Apparatus as claimed in claim 4, wherein said operating means comprises aswitch secured in fixed position, abutment means secured to said second conduit for movement therewith, said abutment means having a bearing surface cooperating with said switch for closing the same when the cap member, and thereby the second conduit, have been displaced to predetermined positions.

6. Apparatus as claimed in claim 5, wherein said uppermost board is at the level of the worktable when the switch is closed.

7. Apparatus as claimed in claim 1, wherein each board includes a lateral extension in which said inlet is located, and internal reinforcing ribs throughout the extent of the board.

8. Apparatus as claimed in claim 3-, comprising sealing means on said cap member for forming a sealed connection between the cap member and the uppermost board at the inlet thereof.

References Cited UNITED STATES PATENTS 3,146,897 9/1964- Curtenius 214+8Js 3,209,924 .10/1965 Hawkes 214--8.5' 

